In order to analyze a fluid, such as blood, filled in a plugged test tube, thereby to determine the presence or absence of bacilli in the fluid, or to identify the bacilli, if any in the fluid, it is necessary to extract the plug, such as a rubber plug, from test tube, and then to divide the fluid into several portions, and finally to supply these portions to various devices for analyzing different test items. As for such analysis devices, research has been made. Analysis devices using high technology have been developed and put to a practical use. However, so-called "pre-processes," such as extraction of plugs, depend exclusively on handwork as is seen in big hospitals. A person takes plugged test tubes containing samples of blood, one by one, and then pulls the plugs thereform. No apparatuses which can automatically extract plugs from test tubes have been provided.
The plug-extracting process, performed by handwork, is accompanied by the possibility that the fluid is split from the tube by mistake when the plug is pulled from the tube, thus wetting the person's hands, dripping onto the floor. The process is also accompanied by the possibility that the test tube is dropped onto the floor and is broken. If these undesirable events happen, the sanitary condition of the room, where this process is carried out, will be impaired. Further, the plug extraction by hand is not efficient. When a great number of test tubes must be opened within a limited time, many persons must work on this process. If sufficient labor force is not acquired, much time is required to complete the plug-extracting process.
It is accordingly the object of the present invention to provide an automatic test tube plug extraction apparatus which can readily extract plugs from test tubes without spilling the fluid from the tubes, wetting a person's hands with the fluid, dripping the fluid onto the floor, or dropping the test tubes onto the floor, thereby preserving the sanitary condition of the room where the plug-extracting process is performed, and which can extract plugs from a great number of test tubes within a short time.